<HTML>
<BODY BGCOLOR="white">
<PRE>
<FONT color="green">001</FONT>    package gates;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    /**<a name="line.3"></a>
<FONT color="green">004</FONT>     * Composite Grover gate.<a name="line.4"></a>
<FONT color="green">005</FONT>     * Basically it is 4 operations: oracle, H, NandAll, H.<a name="line.5"></a>
<FONT color="green">006</FONT>     * where the oracle marks the searched state, H is a hadamard transform of all qubits and NandAll is<a name="line.6"></a>
<FONT color="green">007</FONT>     * a function does the nand operation on all states (flips all states except ground state).<a name="line.7"></a>
<FONT color="green">008</FONT>     * This method was taken from &lt;a href="http://www.hpl.hp.com/breweb/quiprocone/Protected/Lecture_6.htm"&gt;Deutch's lectures on quantum computing&lt;/a&gt;<a name="line.8"></a>
<FONT color="green">009</FONT>     * and from &lt;it&gt;An Introduction To Quantum Computing: Kaye et al&lt;/it&gt;<a name="line.9"></a>
<FONT color="green">010</FONT>     * @author Jan Zaucha, Alex Bush<a name="line.10"></a>
<FONT color="green">011</FONT>     *<a name="line.11"></a>
<FONT color="green">012</FONT>     */<a name="line.12"></a>
<FONT color="green">013</FONT>    public class GroverComposite extends CompositeGate {<a name="line.13"></a>
<FONT color="green">014</FONT>    <a name="line.14"></a>
<FONT color="green">015</FONT>            /**<a name="line.15"></a>
<FONT color="green">016</FONT>             * Construct the grover gate. Calls the super class Composite Gate<a name="line.16"></a>
<FONT color="green">017</FONT>             * @param searched Element that is searched in the algorithm<a name="line.17"></a>
<FONT color="green">018</FONT>             */<a name="line.18"></a>
<FONT color="green">019</FONT>            protected GroverComposite(int searched, int numQubits) {<a name="line.19"></a>
<FONT color="green">020</FONT>                    super(getGates(searched, numQubits));<a name="line.20"></a>
<FONT color="green">021</FONT>            }<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>            <a name="line.23"></a>
<FONT color="green">024</FONT>    <a name="line.24"></a>
<FONT color="green">025</FONT>            /**<a name="line.25"></a>
<FONT color="green">026</FONT>             * Private method to provide the array of gates used in the Grover algorithm<a name="line.26"></a>
<FONT color="green">027</FONT>             * @param searched Element that is searched<a name="line.27"></a>
<FONT color="green">028</FONT>             * @return groverIteration Array of gates creating the grover iteration.<a name="line.28"></a>
<FONT color="green">029</FONT>             */<a name="line.29"></a>
<FONT color="green">030</FONT>            private static Gate[] getGates(int searched, int numQubits){<a name="line.30"></a>
<FONT color="green">031</FONT>                    Gate oracle = Factory.createOracle(searched);<a name="line.31"></a>
<FONT color="green">032</FONT>                    Gate hadamardTransform = Factory.createHadamard(-1);<a name="line.32"></a>
<FONT color="green">033</FONT>                    Gate nand = Factory.createNand(numQubits);<a name="line.33"></a>
<FONT color="green">034</FONT>                    Gate [] groverIteration = new Gate [4];<a name="line.34"></a>
<FONT color="green">035</FONT>                    groverIteration[0] = oracle;<a name="line.35"></a>
<FONT color="green">036</FONT>                    groverIteration[1] = hadamardTransform;<a name="line.36"></a>
<FONT color="green">037</FONT>                    groverIteration[2] = nand;<a name="line.37"></a>
<FONT color="green">038</FONT>                    groverIteration[3] = hadamardTransform;<a name="line.38"></a>
<FONT color="green">039</FONT>                    return groverIteration;<a name="line.39"></a>
<FONT color="green">040</FONT>                    <a name="line.40"></a>
<FONT color="green">041</FONT>    }<a name="line.41"></a>
<FONT color="green">042</FONT>            <a name="line.42"></a>
<FONT color="green">043</FONT>            /**<a name="line.43"></a>
<FONT color="green">044</FONT>             * Return the name of this gate<a name="line.44"></a>
<FONT color="green">045</FONT>             */<a name="line.45"></a>
<FONT color="green">046</FONT>            public String getName() {<a name="line.46"></a>
<FONT color="green">047</FONT>                    return "Grover Iteration";<a name="line.47"></a>
<FONT color="green">048</FONT>            }<a name="line.48"></a>
<FONT color="green">049</FONT>    }<a name="line.49"></a>




























































</PRE>
</BODY>
</HTML>
